View Full Version : Factory Alarm acting up

01-21-2005, 12:23 AM

I have an '89 SC with the factory alarm system. The problem I am having is that the alarm goes off if I unlock the doors using the keyless entry keypad which will not let my car start. If I go back and unlock the doors with the key, it shuts the alarm off. Anyone had any experience with this? Any help would greatly be appreciated.

01-21-2005, 02:00 AM
The signal from the keyless entry to open the driver's door lock and to disarm the alarm is sent via red-orange wires from the keyless entry module to the driver's door lock actuator and the anti-theft module.
If you have verified that the driver's door can be locked and opened using the keypad (by pulling on the door handle and by hearing a click from the actuator), then the keyless entry module is probably working properly and sending the correct signal to the lock actuator. This will mean that the signal is either not reaching the anti-theft module or the module itself is bad. If you have a voltmeter, get someone to operate the keypad and at the same time compare the signals at the red-orange wire to the keyless entry module and the red-orange wire to the anti-theft module. Both modules are attached to the rear side of the vertical plastic panel inside the trunk on the left fender. If the signals are not the same even with the anti-theft module unplugged, then you have a loose connection somewhere along this wire. If the signals are the same, or you don't have a voltmeter, then replace the anti-theft module.